Methods for coating conducting polymer

Abstract

Polypyrrole (PPy) is one of the most commonly studied conducting polymers due to its good stability, high conductivity, ease of preparation and non-toxicity. The stability of the conductivity of polypyrrole films depends on the choice of dopant anion, the method of preparation, and the conditions of aging. Most of the existing methods only improve stability by sacrificing conductivity, as well as sensitivity. This invention provides a method for coating conducting polymer onto a substrate by first applying an anionic dopant and an oxidizing agent onto the substrate. The monomer is then allowed to form the conducting polymer at about -10 to -80.degree. C. for a sufficient period of time. After storage for a long period of time (nearly a year), the conductive polymer coating still retains almost the same strain sensitivity and at least up to 85% of its initial conductivity.